Does chlorine really kill all the pee in the pool?

Does chlorine really kill all the pee in the pool?

Peeing in the pool is not exactly the most hygienic habit, yet most adults, and even Olympic swimmer Michael Phelps, admit to “letting it flow” in the pool. It seems so harmless being surrounded by chlorinated water with plenty of chemicals to keep it clean. But peeing in the pool may not be so harmless.

According to research published in the journal Environmental Science & Technology, urinating in the pool may pose more serious health risks than you think. The study found that the uric acid in urine creates dangerous byproducts in the pool as it interacts with the chlorine. These byproducts, cyanogen chloride (CNCI) and trichloramine (NCI3),are known to have detrimental effects on lung health.

According to the research findings, more than 90 percent of uric acid found in swimming pools comes from human urine, which is concerning given that uric acid can lead to the formation of such toxic compounds. Most of the time the concentrations of these chemicals in a swimming pool remains low, but there are times, such as when a pool is being used heavily, that the levels can rise.

“A large swimming event or crowded pool, that’s the circumstance that concerns me the most,” said study author Ernest R. Blatchley III, a professor of civil engineering at Purdue University in West Lafayette, Ind., in a statement.

“Clearly people swim in pools every day and don’t get sick, and while not everyone will become ill, some people might develop acute illnesses or chronic problems, explains Dr. Phillip Favia, a family medicine doctor at Advocate Good Shepherd Hospital in Barrington, Ill. “There really are two simple ways to lower the levels of uric acid and other chemicals found in sweat and urine in a pool. Shower before you enter the pool, and leave the pool if you need to urinate. It’s safer for everyone, including yourself.”

Dr. Favia explains that swimming is an excellent form of exercise and shouldn’t be avoided or considered unhealthy due to this research.

“Most people that go swimming don’t get sick at all,” he says. “If more people left the pool to use the bathroom, they can help make swimming that much healthier for the others.”

The CDC has the following tips for staying germ-free in the pool:

o    Don’t swim when you have diarrhea.

o    Shower with soap before you start swimming.

o    Take bathroom breaks every 60 minutes.

o    Wash your hands after using the toilet or changing diapers.

o    Don’t swallow the water you swim in.

“The simplest advice I can give is not to urinate in the pool, and second, you might consider skipping the kiddie pool,” Dr. Favia says.

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  1. Ick! I had no idea. Will be sure to pass this message around so everyone can safely enjoy clean pool water!

  2. This kind of makes me never want to go in a pool ever again.

  3. Lisa Parro


  4. I hope no one is peeing in my pool!

  5. In the past I’ve had a few less than acceptable maintenance services for my pool. A few months ago, a friend suggested I try Miami Pool Tech in South FL. I did, and I’m happy to say that their services are excellent. They were professional, friendly, and very responsive to all my concerns and questions. If you’re looking for a great pool maintenance service, check them out at

  6. As an additional yuk – I didn’t realise that you can also get conjunctivitis from swimming in a public pool. I had really bad case3 wks ago & told not to swim. I chlorine is meant to kill bugs why doesn’t it knock this down.

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health enews Staff
health enews Staff

health enews staff is a group of experienced writers from our Advocate Aurora Health sites, which also includes freelance or intern writers.